1. Field of the Invention
The present invention relates to a process cartridge which is provided to be attachable to and detachable from an image forming apparatus, such as a laser printer or a copying machine, a photoreceptor-drum unit which is provided in the process cartridge, an end member which is mounted on a photoreceptor drum of the photoreceptor-drum unit, and a bearing member which configures the end member.
2. Description of the Related Art
In an image forming apparatus, such as a laser printer or a copying machine, a process cartridge which is attachable to and detachable from an image forming apparatus body (hereinafter, referred to as an “apparatus body”) is provided.
The process cartridge is a member which forms contents to be expressed by letters or figures and transfers the contents to a recording medium, such as a paper sheet, and here, includes a photoreceptor drum in which the transferred contents are formed. Therefore, in the process cartridge, various means for forming the contents to be transferred to the photoreceptor drum are disposed together. Examples of these means include means for developing, means for charging the photoreceptor drum, and means for cleaning the photoreceptor drum.
In case of the process cartridge, the same process cartridge is attached to and detached from the apparatus body for maintenance, or a new process cartridge is mounted on the apparatus body by detaching an old process cartridge from the apparatus body in order to replace the process cartridge with a new process cartridge. Attaching and detaching the process cartridge in this manner is performed by users of the image forming apparatus manually, and it is desirable to easily perform attaching and detaching as much as possible from such a point of view.
However, a drive shaft of the apparatus body is engaged with the photoreceptor drum which is included in the process cartridge directly or via another member, and according to this, the photoreceptor drum receives a rotating force from the drive shaft and rotates. Therefore, in order to attach and detach the process cartridge to and from the apparatus body, it is necessary to release (detach) the engagement between the drive shaft of the apparatus body and the photoreceptor drum, and to reengage (mount) the process cartridge again.
Here, if it is possible to move the photoreceptor drum (process cartridge) in a direction of an axial line of the drive shaft of the apparatus body, and to attach and detach the photoreceptor drum, configuring an apparatus for this can be relatively easy. However, from the viewpoint of reducing the size of the image forming apparatus or ensuring space for the attachment and detachment of the process cartridge, it is preferable that the process cartridge is detached from the apparatus body and falls out in a direction which is different from the axial line direction of the drive shaft, and that mounting the process cartridge to the apparatus body is done by pushing in this direction.
In JP-A-2010-26473 as Patent Literature 1, a structure for attaching and detaching a process cartridge in a direction which is different from an axial line direction of a drive shaft of an apparatus body is disclosed. Specifically, a coupling member (shaft member) which is disclosed in JP-A-2010-26473 as Patent Literature 1 is swingably attached to a drum flange (bearing member) by providing a spherical section. Therefore, a part (rotating force receiving member) which is provided in the coupling member and engages with the drive shaft of the apparatus body can swing around the spherical section, an angle with respect to the axial line of the photoreceptor drum can be changed, and engagement and disengagement between the drive shaft of the apparatus body and the photoreceptor drum become easier.
In addition, in Japan Institute of Invention and Innovation Journal of Technical disclosure, Japan Institute for Promoting Invention and Innovation No. 2010-502200 as Non Patent Literature 1, a structure in which a groove for attaching a rotating force transmission pin provided in a shaft member to a bearing member is provided in a rotating direction of an inner circumference of the bearing member, and attachment of the rotating force transmission pin to the bearing member is easily performed due to the groove, is disclosed.    Patent Literature 1: JP-A-2010-26473    Non Patent Literature 1: Japan Institute of Invention and Innovation Journal of Technical disclosure, Japan Institute for Promoting Invention and Innovation No. 2010-502200